Binary numbers

The sum of the binary numbers (1101001) and 0101100 results in the decimal equivalent of??

Compressive stress

WOULDN'T I NEED TO KNOW THE LENGTH OF THE BAR IN THE BELOW FORMULA OR AM I INCORRECT? A circular cross sectional bar with a diameter of 3.25 inches is loaded with a uniform axial compressive load of 22,750 pounds. What is the compressive stress along a cross section of the bar...in PSI?

Stereographic projection on complex plane

Let V be a circle lying in S. Then there is a unique plane P in R^3 such that p /\ S = V ( /\ = intersection). Recall from analytuc geomerty that P = { (x_1,x_2,x_3) : x_1 b_1 + x_2 b_2 + x_3 b_3 = L, where L is a real number}. Where ( b_1,b_2,b_3) is a vector orthogonal to P . It can be assumed that (b_1)^2 + (b_2)^2 + (b_3)^2=1. Use this information to show that if V contains the point N then its seteographic projection on the complex plane is a straight line. Otherwise, V projects onto a circle in complex plane. N = (0,0,1) the north pole on S Please explain to me every step, I don't just want the answer, but I also want to understand it and be able to work similar problems.

Metric spaces and the topology of Complex plane

Show that { cis k : k is a non-negative ineger} is dense in T = { z in C ( C here is complex plane) : |z| = 1 }. For which values of theta is { cis ( k*theta) : K is a non-negative integer} dense in T ? P. S. cis k = cos k + i sin k, i here is square root of -1. I want a full justification for each step or claim.

Upper half plane

Please see attached