Two vectors and  are given by  and

style="vertical-align:middle;" src="https://sciemce.com/media/2/ppg__cognero__Chapter_9_Energy_in_Nonisolated_Systems.__media__bf8af0f8-35eb-471f-a479-9b4f159e5328.PNG" data-wiris-created="true" class="Wirisformula" align="middle" />. The scalar product of  and a third vector  is ?16. The scalar product of  and  is +18. The z component of  is 0. What is the magnitude of ?

A. 7.8
B. 6.4
C. 3.6
D. 5.0
E. 4.8

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Answer: C

Physics & Space Science

Projectile Motion: An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 35° above the horizontal. How long does the athlete stay in the air, assuming no significant air resistance?

A. 0.50 s B. 0.88 s C. 1.1 s D. 2.5 s E. 0.54 s

The study of all aspects of the atmosphere is called ______________

Fill in the blank(s) with correct word

The diffusion constant for oxygen through water is What is the time for an oxygen molecule to diffuse 1 cm?

a.
b.
c.
d.
e.

What can we detect from matter that has crossed an event horizon?

A) Gamma-ray bursts B) Radio waves if the matter was traveling fast enough C) Visible light D) X-rays if the matter was dense E) Nothing