During a laboratory experiment, a student finds
that at 20° celsius, a 6.0-meter length of copper
wire has a resistance of 1.3 ohms. the crosssectional
area of this wire is
(1) 7.9 × 10^−8 m2 (3) 4.6 × 10^0 m2
(2) 1.1 × 10^−7 m2 (4) 1.3 × 10^7 m2

ρ = resistivity of copper at 20 °C = 1.72 x 10⁻⁸ ohm-m

R = resistance of the copper wire = 1.3 ohm

L = length of the copper wire = 6 meter

A = area of cross-section of the copper wire = ?

Resistivity of copper wire is given as

R = ρL/A

inserting the values in the above equation

1.3 = (1.72 x 10⁻⁸) (6)/A

A = 7.9 x 10⁻⁸ m²

Hence the correct choice is

(1) 7.9 x 10⁻⁸ m²

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

hope this : )

radiation

explanation:

heat is transmitted by radiation