Simplify the expression secx/sinx - sinx/cosx

Airline passengers arrive randomly and independently at the passenger-screening facility at a major international airport. The mean arrival rate is 11 passengers per minute.

If ${\displaystyle \sin x+\sin y=a\text{and}\cos x+\cos y=b}$ then find ${\displaystyle \tan (x-\frac{y}{2})}$

How do you find the exact value of ${\displaystyle {\cos }^{-1}0}$

Please, evaluate ${\displaystyle \tan (-30)}$

The base of a pyramid covers an area of 13.0 acres (1 acre =43,560 ${\displaystyle f{t}^2}$) and has a height of 481 ft . Ifthe volume of a pyramid is given by the expression $V=(\frac{1}{3})$bh, where b is the area of the base and his the height, find the volume of this pyramid in cubicmeters.

Solve for ${\displaystyle \theta }$.
${\displaystyle \tan \left(2\theta \right)-\tan \left(2\theta \right){\tan }^2\left(\theta \right)=2}$

Consider the non-triangle shown below that has side lenghts of 1.6, 1.751 and 2.6 cm and interior angle measures of 0.72, alpha and beta degrees.
What is value of alpha and beta