The mid-atlantic ridge crosses through iceland. physical features such as tensional fractures and cinder cone volcanoes are all aligned ne-sw. what does this indicate about the directions the tectonic plates are moving?

This indicates that they are moving away from each other, meaning that they form a divergent plate boundary, between the two continental plates, the Eurasian Plate moving eastward, and the North American Plate moving west, this forms the Mid Atlantic Ridge.

A. to determine if humans can explore mars safely

Since you have not included the experiment situation and the data, of course, i can not give you specific details about it. but i can you with this question.1) i will assume that the motion is projectile (parabolic) motion.2) yes, the horizontal distance depends on the horizontal velocity as, naming vx the horizontal velocity and t the time, it is: x = vx × t3) now, observe that the flight time depends on the vertical velocity as, naming voy the initial vertical velocity, t the time and y the vertical distance before reaching the ground: y = yo + voy×t - gt² / 2.the higher the initial vertical velocity (voy) the longer the object will be flying and so t will be higher in the equation for the horizontal distance.that explains the relationship between the horizontal distance and the horizontal velocity.