The area of a telescope lens is 6.676 x 10 mm. (a) what is the area in square feet (ft)? enter your answer in scientific notation. x 10ft (b) if it takes a technician 51.7 s to polish 1.46 x 10mm', how long does it take her to polish the entire lens?

a) A = 7.186 E-4 ft²

b) t = 236.403 s

Explanation:

A = 6.676 E1 mm²

a) A = 6.676 E1 mm² * ( ft / 304.8 mm )²

⇒ A = 7.186 E-4 ft²

b) t = 51.7 s → A = 1.46 E1 mm²

⇒ relation (r) = 6.676 E1 mm² / 1.46 E1 mm² = 4.573

⇒ t = 51.7 s * 4.573 = 236.403 s

a c d and f

just finished the assignment

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.