Iwas planting a tree in my backyard and hit something hard. i dug it out and decided it was an ore of copper. i took its mass, and it was 65.0 grams. after some tricky experiments in my basement lab, i managed to extract 11.5 grams of copper. what is the mass percent of copper in the ore i discovered? a.63.5%b.18.1%c.5.65%d.17.7%

option (d) 17.7%

Step-by-step explanation:

Data provided in the question:

Mass of the ore of copper extracted from the backyard = 65.0 grams

Mass of the copper extracted from the ore of copper = 11.5 grams

Now,

The mass percent of copper discovered

= [ ( Mass of the copper extracted ) ÷ ( Mass of the copper ore extracted ) ] × 100%

= [ 11.5 grams ÷ 65.0 grams ] × 100%

= 17.692% ≈ 17.7%

Hence,

the answer is option (d) 17.7%

step-by-step explanation:

we are given

since, we have to isolate x on anyone side

so, we can move all x terms on one side

subtract both sides by 2x

add both sides by 9

divide both sides by 4

we get

answer is the third choice:

3x^5+4x^4+x^3+2x^2-10x-7=0

step-by-step explanation: