Answer:
735 J/kg/C
Explanation:
Q = mcT
943 = (0.447)( c )(2.87)
1.28289c = 943
c = <u>7</u><u>3</u><u>5</u><u> </u><u>J</u><u>/</u><u>k</u><u>g</u><u>/</u><u>C</u><u> </u><u>(</u><u>3</u><u> </u><u>s</u><u>f</u><u>)</u>
Answer:
<em>The magnitude of vector d is 16 and the angle with the x-axis is 270°</em>
Explanation:
<u>Operations With Vectors</u>
Given two vectors in rectangular components:

The sum of the vectors is:

The difference between the vectors is:

The magnitude of
is:

The angle
makes with the horizontal positive direction is:

The question provides the vectors:



Calculate:

The magnitude of
is:

The angle is calculated by:

The division cannot be calculated because the denominator is zero. We need to estimate the correct angle by looking at the components of the vector. Since the x-coordinate is zero and the y-coordinate is negative, the vector points downwards (south), thus the angle must be -90° or 270° if the range goes from 0° to 360°.
The magnitude of vector d is 16 and the angle with the x-axis is 270°
<span>Scientists have documented that the current level of carbon dioxide in the atmosphere is increasing.</span>
We know, U = m * g * h
U = 4000 * 9.8 * 20
U = 784000 J
In short, Your Answer would be: 784000 J or 784 KJ
Hope this helps!