Please help me for branllest

What is the length x of the side of the triangle below? (hint: use the cosine function)

Find the equation for the plane through upper p 0 left parenthesis negative 4 comma negative 8 comma negative 5 right parenthesis perpendicular to the following line. xequalsnegative 4 minus t, yequalsnegative 8 plus 2 t, zequals3 t, minusinfinityless thantless thaninfinity

When measuring volume, why is it important to use the correct tools and units to attain the greatest accuracy? use specific examples from the lab to support your answer. (5 points)