Given point P(-2, 6, 3) and vector a=ᵧaₓ+(x+z)aᵧ, express P and a in spherical coordinates. Evaluate a and P in the spherical system.
a. a=3aᵣ+4aθ+5aϕ, P=(7,109.5°, 54.74°)
b. a=3aᵣ+5aθ+4aϕ, P=(7,54.74°,109.5°)
c. a=4aᵣ+3aθ+5aϕ, P=(7,109.5°, 54.74°)
d. a=5aᵣ+3aθ+4aϕ, P=(7,54.74°, 109.5°)