If    find the units of a, b and c. when( x) in  m  and (t) in  sec.

If x(t) is measured in meters (m) and t is measured in seconds (s), then we must have such that the units remain consistent:

For this to happen, we need s to cancel in the first term and produce a length in m; for this, we would get a in m/s.

In the second term, s^2 needs to be canceled, so b has unit m/s^2.

In the third term, s^3, so c has unit m/s^3.

1 - wave length

2 - amplitude

3 - crest

4 - trough

explanation:

duh.