The sedimentary rock in question is sandstone.
Sandstone is a clastic sedimentary rock made up mostly of weathering sand size debris that accumulates where the waters are slower.
Sandstone is formed by all of the processes named above.
-weathering of the rocks
-erosion caused by water and wind
-transportation by water bodies
-deposition by the water masses where they are slower
-lithification under the pressure
-compactation while mixing with multiple other sediments.
I would say that Jomo Kenyatta was the first at least black Prime Minister in 1963-64 and then became Kenya's President when it became a republic after the anti-British colonial movement expelled the British, He was President from 1964-1978. He fought strongly against the British colonialists and for independence.
Because the index fossils help with approximate yearing and rock layers tell which is older and ypunger
A & b one of them are right