I have no idea about this problem solving, don't know where to start or how to go about it.. Could someone please help me with these questions? Any help would be HUGELY appreciated Thank you!

1. )You are watching the sunset in July on a west-facing beach in a country on the equator (say

Gabon). Behind the beach there is a cliff, 30 meters high. As soon as the sun has disappeared

behind the horizon you start a timer and run to the top of the cliff, where the sun is still visible.

You watch the sunset again from the cliff and stop the timer when the sun disappears behind

the horizon. The reading on the timer is 42.2 seconds. Use this information to estimate the radius of the earth.

2.) Give estimates of the following quantities Justify your answer!

(a) The number of (working) hairdressers in Edinburgh,

(b) The number of grains of sand on (mainland) Spanish beaches (not counting sand which is

permanently covered with water),

(c) The energy that could be generated per year if a every Munro was equipped with a

hydroelectric power plant.

(d) The total annual domestic energy consumption in Scotland