Answer
given,
F₁ is horizontal = 40 N
F₂ is normal = 20 N
F₃ is parallel = 30 N
work done by
W₂ = 0 as force is acting perpendicular to the direction of motion.
as the motion moved to 0.8 cm
W₃ = F₃ x d
W₃ = 30 x 0.8
W₃ = 24 J
W₁ = F₁ x d
W₁ = F₁ cos ∅ x d
W₁ = 40 cos 30⁰ x 0.8
W₁ = 27.21 J
The answer is the first option "true." According to social exchange theory, altruistic behaviors benefit the individual who performs them is a true statement. That is because the word Altruism means doing acts to benefit themselves.
Hope this helps.
The Curiosity rover launched<span> on a two-stage Atlas V-541 </span>launch<span> vehicle, provided by United </span>Launch<span>Alliance, a joint venture of Boeing Co. and Lockheed Martin Corp.</span>
-- A little girl has a voice with high pitch (high frequency)
-- Speaking quietly, she's making sounds with low amplitude
The wave with the high frequency and low amplitude is <em>C</em> .
