Explain the answer and do not use chat gpt$,$ otherwise i will downvote.

$(1)$ The curvature of earth is ignored in

a$)$ Geodetic surveying

c$)$ Plane surveying

b$)$ Hydrographic surveying

d$)$ Astronomical surveying

$(2)$ The true meridian passes through

a$)$ Geographical poles

c$)$ Magnetic poles

b$)$ Arbitrary poles

d$)$ only N$-$pole