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How are proteins synthesised?

Proteins are coded for by genes (a sequence of DNA that codes for a specific polypeptide), in the nucleus the DNA is unwound by an enzyme and then another enzyme with copy the template strand to make a molec...
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Answered by Billy R. • Biology tutor
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The price of coffee beans rose from $1.15 to $1.40 between June and August 2017. A possible cause of this rise is: a) Improved weather conditions in coffee-growing countries; b) An increase in national minimum wage in coffee growing countries.

The correct answer is b).The price mechanism is defined as the interaction between supply and demand for a good, which determines price such that quantities supplied and demanded are equal.An increase in nat...
GS
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Acid HA has a Ka of 2.00 x 10-4mol dm-3. A solution was made by adding 15cm3 of 0.34 M NaOH to 25cm3 of 0.45M HA. Calculate the moles and the concentration of A- and HA in this solution. Using the expression for Ka calculate the pH of the solution

Write the equation : NaOH + HA --> NaA + H 2 O. Find the moles of A - : the moles of A - = the moles of NaOH added. 15 x 10 -3 x 0.34= 5.10 x 10 -3 . Workout the initial moles of HA : 25 x 10 -3 x 0.45= 0...
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Answered by Hibba S. • Chemistry tutor
7520 Views

How would you calculate the vertical and horizontal components of the velocity of an object with an initial velocity of 15m/s which is travelling upwards at an angle of 30 degrees to the horizontal?

With these sort of questions involving components, I would always advise drawing a diagram of the problem so that you're clear of the situation!In this case we have an object that is travelling at a speed of...
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Answered by Joseph P. • Physics tutor
7458 Views

An excess of Lead (II) oxide reacts with 175cm3 of 1.5 mol dm3 nitric acid. Calculate the maximum quantity of lead that can be obtained from this reaction.

Write the equation: PbO + HNO 3 --> PbNO 3 + H 2 O. Balance the equation: there are two moles of hydrogen (in water) on the right. To balance the hydrogens, two moles of hydrogen are needed on the left to...
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Answered by Hibba S. • Chemistry tutor
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