Hola! No se si buscaste antes por aquí pero ya hay una respuesta anterior a esta pregunta y es la opción D
Caves are formed by the dissolution of limestone. Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves.
(a)
We can see that
this is a straight line
and this is the graph of velocity
we know that
acceleration is the derivative of velocity
so, slope of curve of velocity is acceleration
so, we will find slope of this line
We can select any two points
(0,4) and (5,7)
we can use slope formula

now, we can plug points


we know that slope of line is always constant irrespective of any value of t
so, acceleration will always be same irrespective of any value of t
so, we will get acceleration
............Answer
(b)
we can see that acceleration is constant
and we know that
derivative of constant is always 0
so, instantaneous rate of acceleration at t=10s is 0........Answer
3 x 6 x 9 x 3 x 6 x 9 = ?
3 x 6 = 18
18 x 9 = 162
162 x 3 = 486
486 x 6 = 2,916
2,916 x 9 = 26,244
3 x 6 x 9 x 3 x 6 x 9 = 26,244
Answer: the answer is 0.078, 0. 708, 0.78, 0.87