How would I input these formulas with given numbers using python?

Part A

The shear stress when a normal stress of 20 is applied to a material with cohesion 2 and angle of internal friction 35 degrees. using The Mohr-Coulomb Failure Criterion

part B

The scattering angle for maximum interference for light of wavelength 7.5 x 10^-7 hitting a crystalline lattice with planes separated by a distance 1 x 10^-6. using Bragg's Law