How many significant figures are there in each of the following? (a) 69.6t 0.4 (b) 3.2 x 109 (c) 2 x 10-6 (d) 0.0028

a) Three significant figures.

b) Two significant figures.

c) One significant figures.

d) Two significant figures.

Explanation:

a) 69.6 ± 0.4

By place decimal below decimal and then adding or subtracting will get 3 significant figures.

69.6 + 0.4 = 70.0

69.6 - 0.4 = 70.2

b)

Two significant figures.

c)

one significant figures.

d) 0.0028

Two significant figures.

d. air pressure decreases as altitude increases.

initial speed when it is dropped is 150 ft/s

now at the same moment the acceleration due to gravity is perpendicular to its velocity

so as we know that

now we have centripetal acceleration a = 32 ft/s^2 as its perpendicular to velocity

while tangential acceleration at the same moment will be zero

so

now radius of curvature is given as

so the radius of curvature just after it is dropped is 703.125 ft