If r(t) is the position vector of a particle in the plane at time t, find the indicated vector.Find the acceleration vector.r(t) = (7 ln(9t))i + (8t3)j

Write the equation for the plane.The plane through the points P(-1, 7, -36) , Q(2, 6, -17) and R(1, -7, 30). 

Solve the problem.Write an iterated triple integral in the order for the volume of the tetrahedron cut from the first octant by the plane .

Solve the problem.A 450-lb sign is hanging from the end of a hinged boom, supported by a cable inclined at 48° with the horizontal. Find the tension in the cable and the compression in the boom rounded to the nearest pound.

Find the unit tangent vector of the given curve.r(t) = 3t2i – 12t2j + 4t2k

Solve the problem. Unless stated otherwise, assume that the projectile flight is ideal, that the launch angle is measured from the horizontal, and that the projectile is launched from the origin over a horizontal surfaceA projectile is fired at a speed of 1040 m/sec at an angle of 39°. How long will it take to get 26 km downrange? Round your answer to the nearest whole number.

Evaluate the line integral along the curve C.ds, C is the curve r(t) = (4 sin t)i + (4 cos t)j + 12tk, 2 ≤ t ≤ 4

During what age range is brain growth the fastest? At what age does the brain finish pruning the prefrontal cortex? 

During what age range is brain growth the fastest? At what age does the brain finish pruning the prefrontal cortex? 

Match the terms with their description.