Paul, colin and brian are waiters. One night the restaurant earns tips totalling £77. 40. They share the tips in the ratio 2:3:4. How much more does brian get over paul?.

Explain how you might determine the rate of weathering on a sample rock

Earth's atmosphere is unique among the planets and is able to support life because it contains a large amount of a) oxygen b) helium c) methane d) carbon dioxide

Luminous objects such as flashlights emit light that we can see. how do we see an object that isn’t luminous? a. the object emits light that reaches our eyes. b. light reflects off the object and reaches our eyes. c. light passes through the object uninterrupted. d. light is fully absorbed by the object. e. we can’t see an object that isn’t luminous.