Answer:
1,2 and 4 are equivalents. 3 is not equivalent
2P-I, mark that one :l
Step-by-step explanation:
Answer:
<h3><em>4 × 3 + 3²</em></h3><h3><em>4 × 3 + 9</em></h3><h3><em>12 +</em><em>9</em></h3>
<em>21</em>
<em>Therefore</em>
<em>A</em><em>n</em><em>s</em><em>w</em><em>e</em><em>r</em><em> </em><em>=</em><em> </em><em>2</em><em>1</em>
<em>h</em><em>o</em><em>p</em><em>e</em><em> </em><em>h</em><em>e</em><em>l</em><em>p</em><em>s</em><em>~</em>
Answer:
15 seconds.
Step-by-step explanation:
∵ The distance covered by plane in first second = 100 ft,
Also, in each succeeding second it climbs 100 feet more than it climbed during the previous second,
So, distance covered in second second = 200,
In third second = 300,
In fourth second = 400,
............, so on....
Thus, the total distance covered by plane in n seconds = 100 + 200 + 300 +400......... upto n seconds
( Sum of AP )
Suppose the distance covered in n seconds is 12,000 feet,
∵ n can not be negative,
Hence, after 15 seconds the plane will reach an altitude of 12,000 feet above its takeoff height.