In a type of fruit fly the brown body colour allele is dominant to the black body colour allele. A male fruit fly heterozygous for body colour and a female…

Which one of the following is a simplification of x/x-1 - x2+3/ x2 +2x-3? Answer:

The radioactive isotope plutonium-244 becomes radon-220 after a succession of decays. The atomic number of plutonium is 94 and the atomic number of radon is 86. How many alpha particles…

A compound of oxygen and fluorine has a relative molecular mass which is twice that of its empirical formula mass. 105 g of the compound contains 57 g of fluorine.…

An animal cell is surrounded by a very dilute glucose solution which has a lower concentration of glucose than the glucose solution in the cytoplasm of the cell. There is…

The mean mass of a sweet in a bag of 20 sweets must be greater than 10 grams but not greater than 10.5 grams. A bag is being filled with…

A circuit consists of a 10 Ω resistor and a variable resistor connected in series with a 6.0 V battery. The variable resistor has a minimum resistance of 2.0 Ω…

Which of the following shows the correct structure of part of the polymer formed by thepolymerisation of CH3 – CH = CH – CH3 ? Answer: 18) E The double…

The diagram shows a simple piece of apparatus that can be used to demonstrate some of the events involved in human ventilation. Which events occurring during ventilation will be demonstrated…