Tom

The curve C is given by the equation y=mx^3-x^2+8x+2, for a constant m.

a) Find dy/dx

The point P lies on C, and has the x-value 5. The normal to C at P is parallel to the line given by the equation y+4x-3=0.

b) Find the gradient of curve C at P.

Hence or otherwise, find:

c i) the value of m

c ii)the y-value of P.

Thanks help will be much appreciated!!

1) If a car salesperson sells more than 3 cars during the week, the probability of taking the next weekend off is 7/8. If 3 or less cars are sold during the week, the probability of taking the next weekend off is 2/5. If the probability of selling more than 3 cars during the week is 1/5, find the probability that the car salesperson will take the next weekend off.

2) A bag contains n counters. Seven of these counters are green and the rest are yellow. Two counters are chosen at random. The probability that the two counters are green is 1/5.

a) Form an equation involving n and show that it simplifies to n^2 - n - 210 = 0

b) Find how many counters were in the bag originally

THANKS HELP WILL BE MUCH APPRECIATED!

1. A computer costs £990 before VAT of 17.5%. What is the cost with VAT?

2. A television costs £446.50 including VAT of 17.5%. What is the cost without VAT?

1. Explain how the Sun is the ultimate source of the energy in:

i) biomass

ii) waves

2. State which energy sources do not originate in the Sun and explain where they come from.

I am really stuck on these questions help will be much appreciated!

Could you please help me translate the following sentences into english, as online translators are nearly always wrong.

1. Pour jouer au tennis, on met un t-shirt et un short.

2. Pour faire du skate, mon frere met un jean.

3. Pour aller au mariage de ma soeur, mes parents et moi, nous mettons nos vetements de fete.

4. Il fait froid, les enfants. Est-ce que vous mettez une veste?

5. Pour aller a la plage, les enfants mettent un short.

6. Quand il pleut, on met une veste.

Thanks help will be much appreciated!!

A regular rectangular piece of card is displaced towards the left, with a pin in the top right hand corner. The centre of gravity is in the middle. The card is released. Describe and EXPLAIN the initial movement of the card. ( 2 marks)

Thanks help will be much appreciated!

A regular rectangular piece of card is displaced towards the left, with a pin in the top right hand corner. The centre of gravity is in the middle. The card is released. Describe and EXPLAIN the initial movement of the card. ( 2 marks)

Thanks help will be much appreciated!

Give all answers correct to 3 Significant figures where appropriate, except question 3.

1. While on special offer, a tin of baked beans contains 25% extra free. If the height of the tin is to remain the same and the area of the base of the original tin is 30cm^2 find the diameter of the new tin.

2. A running track consists of two straight sections with semi-circular ends. If the straight sections measure 100 metres and one complete lap on the inside of the track measures 0.5 km, what is the distance x between the two straights?

3. A rope 60m long and 5cm in diameter is coiled tightly. Estimate, correct to one significant figure, the radius of the 'circle' formed.

I am really STUCK on these questions HELP will be greatly appreciated THANKS!

1. 2/x+2 - x/(x+2)^2

2. 2/x^2+x - 4/x

help will be appreciated!

1. If sulphur dioxide is dissolved in water, what pH would the resulting solution have?

2. If silver nitrate was added to an aqueous solution of potassium bromide, what would you notice?

Help will be much APPRECIATED!!

1. Explain why a mechanic should use a long spanner to undo a tight nut.

2. A mechanic exerts a force of 200N at the end of a spanner of length 200cm. What is the moment (turning effect) applied to the nut?

Use the following words to complete the sentences underneath. Each word may be used more than once or not at all

decomposed

carbon

organisms

bodies

respiration

atmosphere

carbon dioxide

fuels

proteins

animals

bacteria

exchanged

fats

sugars

atmospheric

biochemicals

fungi

compounds

fossil

rare

cycle

plants

1. Although relatively rare in air, atmospheric Carbon dioxide is the main source of carbon for living systems. It is taken up by ........... during photosynthesis, incorporated initially into ................ , and then converted to innumerable other ................ .

2. Dead organisms are .................... by the action of small animals and then .............. and ............... . Their respiratory activity completes the cycle by releasing ............. into the atmosphere.

Help will be much appreciated thanks so much!

Complete the following paragraph using the words provided below. Each word may be used more than once or not at all.

Porous

Surfaces

condenses

30%

soil

environment

sweating

living

animals

90%

transpiration

major

vapour

lakes

cycled

precipitation

atmosphere

absorb

drains

60%

evaporation

rain

plants

foods

Water is a (1) ........ component of all living systems (even people are (2) ........ water). It is (3) ......... both through (4) .......... systems and the non-living parts of the (5) .............. . Water falls as (6) ........... from the clouds. This then (7) .............. of the ground into rivers (8) ......... and seas, and into the (9) ............. and underlying rocks if they are (10) ................. . Plants (11) ............ water through their roots, whereas (12) ........... drink and eat (13) .................. which are rich in water. Water returns to the (14) .............. by (15) ..................... . This occurs directly from the (16) ............... of lakes and seas, via (17) .................... from the leaves of plants and by the breathing and (18) ................. of animals. The water (19) ............... formed then (20) ............... to form clouds from which (21) .................. can then fall again.

1. Explain why India with a higher GNP than South Africa is actually a poorer country.

2. Explain why economic growth and development are not always the same

The isotopes of potassium are shown below:

39 40

K K

19 19

a) Explain how the atomic structure of these isotopes are similar and how they are different.

2. The following letters represent elements. Write down two pairs of isotopes.

197 79 40 40 39 14 14 12

A B C D E F G H

79 34 19 18 19 6 7 6

The equation below shows a reaction between an element x, and water. The Total relative formula mass of the products is 114. What is substance x ?

2X + 2H2O -------> 2XOH + H2

Help will be much appreciated I am so stuck on this question thanks!!!

A space probe lands on the icy surface of Europa, a moon of Jupiter. It weighs a set of known masses, but the readings are not very accurate. Plot a graph of weight against mass using the information below, AND USE IT TO ESTIMATE THE STRENGTH OF EUROPA'S GRAVITY.

Mass Weight

0.1 kg 0.15 N

0.2 kg 0.30 N

0.3 kg 0.36 N

0.4 kg 0.55 N

0.5 kg 0.68 N

How do I use the graph to estimate the strength of Europa's gravity??? Please help I am stuck?

1. Two mad scientists are planning a trip to Mars. Professor White tells Professor Brown - "WE DONT NEED SO MUCH FUEL FOR THE RETURN TRIP - THE ROCKET WILL HAVE LESS MASS ON MARS.

Is Professor White's reasoning correct? Explain your answer. (Ignore the fuel burned reaching Mars)

2. Professor Brown wants to investigate gravity on Mars. He takes to Mars a small fire extinguisher which weighs 50 N on Earth. He also takes his bathroom scales.

On Mars, Professor Brown weighs the fire extinguisher. The scales read 1.9kg. Calculate the ACCELERATION DUE TO GRAVITY on Mars.

I am so stuck on these questions please help??

1. Two mad scientists are planning a trip to Mars. Professor White tells Professor Brown - "WE DONT NEED SO MUCH FUEL FOR THE RETURN TRIP - THE ROCKET WILL HAVE LESS MASS ON MARS.

Is Professor White's reasoning correct? Explain your answer. (Ignore the fuel burned reaching Mars)

2. Professor Brown wants to investigate gravity on Mars. He takes to Mars a small fire extinguisher which weighs 50 N on Earth. He also takes his bathroom scales.

On Mars, Professor Brown weighs the fire extinguisher. The scales read 1.9kg. Calculate the ACCELERATION DUE TO GRAVITY on Mars.

I am so stuck on these questions please help??