How did railroads have an advantage over canals and roads in the early 1800s?
a.
they were less expensive to build and operate.
b.
they could haul heavy goods and people more quickly.
c.
they were not hampered by timetables or regulations.
d.
they had a better safety record than canal boats.

angle a = 40.6°

step-by-step explanation:

for any right angle triangle we know the pythagoras theorem reveals

hypotenuse² = height²+base²

by this formula we will calculate the length of hypotenuse

h² = 6²+7²

⇒ h =√36+49 = √85 = 9.22

now from the given triangle sin a = height/ hypotenuse

                                                sin a = 6/9.22 = 0.651

therefore

so angle a = 40.6°

the answer would be logic.