How many significant figures are in the number 123.97

5 significant figures

Step-by-step explanation:

Any first number than starts with > 0, it is counted as significant figures and with 0 in the middle of number, also will be counted. But if the first number is 0, you have to skip to the next number.

e.g

0.0567 = 3s.f

1.542 = 4s.f

0.0000012 = 2s.f

1200586 = 7s.f

87000000002 = 11s.f

A=20,000 m2 per year

Step-by-step explanation:

we have that Volume (V) =300,000 m3, so V=A*h, where A=area (m2) and h=15m

V=A*h ⇒ 300,000m3=A*15m ⇒ A=300,000m3/15m ⇒ A=20,000 m2