Help with give brainliest 20 points

Initially, a particle is moving at 5.33 m/s at an angle of 37.9° above the horizontal. two seconds later, its velocity is 6.11 m/s at an angle of 54.2° below the horizontal. what was the particle's average acceleration during these 2.00 seconds in the x-direction (enter first) and the y-direction?

Which is not true about oxygen-17 and oxygen-18?

In science and physics what is the standard unit of measure for speed?