An unconformity, or abnormality in the layers of rocks, signifies that the process of layering was somehow interrupted. The only feasible choice for this would be (B), where erosion would have interrupted the layering process.
Answer:
a) 141.6m
b) 8.4m/s
Explanation:
a) to find the total displacement you use the following formula for each trajectory. Next you sum the results:

hence, the total distance is 141.6m
b) the mean velocity of the total trajectory is given by:

hence, the mean velocity is 8.4 m/s
Their inferences are based on evidence that they collect during their investigations. Readers learn that scientists gather and interpret evidence and draw conclusions based on this evidence. ... Once scientists have gathered evidence, they use it to make inferences about the things they are investigating.
A moment causes a rotation about or axis. If the moment is to be taken about a point due to a force F, then in order for a moment to develop, the line of action cannot pass through that point...... the total moment was zero because the moment arm was zero as well