What happens when the data in an investigation do not support the original hypothesis?
a. the hypothesis is revised.
b. the scientist gives up and starts an investigation on a new topic.
c. the data are altered so that they support the original hypothesis.
d. the data must be incorrect and are thrown out.

Planck decided to assume that atoms could only vibrate at certain frequencies that were whole numbers eg 2f, 3f and so on. others used to think that atoms vibrate continuously

The boat's velocity relative to the riverbank can be resolved into two components. the component going north is 2.7 m/s and the component going west is 1.2 m/s.we add these two vectors and then find the magnitude of the resultant to get the speed.the magnitude of the resultant vector from adding can be obtained by the pythagorean theorem.    to two significant figures, the boat's speed relative to the riverbank is 3.0 m/s.