Seismic waves
Step-by-step explanation:
An earthquake releases energy as shock waves, the so-called seismic waves, which ripple across the earth's surface. The seismic waves created as they move from the epicentre an earthquake vary.
(from Google)
2^4-1 so 2•2•2•2=16 and 16-1 is 15
Answer:
A) Rational
B) Irrational
C) Rational
D) Irrational
Step-by-step explanation:
Irrational numbers cannot be expressed as a ratio of two number, whereas rational numbers can be. 81 can be expressed as 9*9 whereas, 89 cannot be expressed as ratio of two numbers.