Wave speed = (wavelength) x (frequency)
= (4 m) x (2 /sec)
= 8 m/sec
The answer is 8.
Hope I helped.
<h2>MULTIPLE CHOICES</h2>

- What is the basic unit of all matter?

- OA neutron
- OB. atom
- OC. electron
- OD. proton
- OE. nucleus

_____
- <u>Atom</u> is the smallest, <u>indivisible unit of a chemical</u> <u>element and the fundamental unit of matter</u>. It consists of a nucleus (neutrons + protons) surrounded by an electron cloud. The <u>atom</u> is the smallest unit of matter that cannot be divided chemically and is a building block with its own set of properties.
<h3>#ProvideUniqueAnswers</h3>
Answer:
A hypothesis is an idea or explanation that you then test through study and experimentation.