In the formula P=2r2tr = 3 x 10-3 t = 2.5 x 10 4Calculate the value of P. Leave your answer in standard form. Answer: 4) D P = 2r²t…

A radioactive isotope X decays into the stable isotope Y with a half-life of 20 s. Which graph correctly shows how the mass (m) of Y present in an initially…

Element Y forms an ion Y 3- with the electronic configuration 2, 8, 8.To which group and period of the periodic table does Y belong? Answer: 2) C The (-3)…

Which one of the following involves active transport? A movement of carbon dioxide into alveoli in the lungsB uptake of alcohol (ethanol) through the lining of the stomachC secretion of…

A car of mass 800kg moves up an incline of 1 in 20 (1 in 20 means for every 20m along the road the car gains 1m in height) at…

Cyclohexene, C6H10, is drawn as: Apply this information for the steroid-type structure shown below to find the total number of carbon atoms in the molecule. Answer: 26) B The first…

The hormonal and nervous systems are often compared because of their similar roles in thebody. Which of the following statements about the two systems are true? 1 The nervous system…

A design is set up by joining the points which are one third of the way along the sides of a square. This forms a second square as shown. This…

In an ornamental fountain, water is squirted vertically upwards through a nozzle by a pump. 5kg of water pass through the nozzle each second, and the water reaches a height…

A student prepared nitrobenzene by the following reaction.C6H6 + HNO3 → C6H5NO2 + H2Obenzene nitrobenzeneStarting with 3.9g of benzene, the student obtained 3.69g of nitrobenzene.What is the percentage yield?(Ar :…