He would try to enter as the tide is rising, and leave as the tide is falling. Those things happen at all different times of day during a month.
Answer: The question has some missing details. The initial velocity given as u = -6.5i + 17j + 13k and the final velocity v = -2.8i + 17j -9.3k.
a) = (1.82i - 9.69k)m/s2
b) magnitude = 9.85m/s2
c) direction = 280.64 degree
Explanation:
The detailed and step is shown in the attachment.
Initially, the spring stretches by 3 cm under a force of 15 N. From these data, we can find the value of the spring constant, given by Hook's law:

where F is the force applied, and

is the stretch of the spring with respect to its equilibrium position. Using the data, we find

Now a force of 30 N is applied to the same spring, with constant k=5.0 N/cm. Using again Hook's law, we can find the new stretch of the spring:
Answer:
9.8m/s
Explanation:
acceleration due to gravity is independent of mass