The of aluminium tells you the amount of energy needed to increase the temperature of
$c_ "Al" = "0.214 cal g"^(-1)""^@"C"^(-1)$
You can thus say that in order to increase the temperature of
Now, you know that your sample has a mass of
$55.5 color(red)(cancel(color(black)("g"))) * "0.214 cal"/(1color(red)(cancel(color(black)("g"))) * 1^@"C") = "11.877 cal"""^@"C"^(-1)$
So, you now know that in order to increase the temperature of
But since you know that the temperature change is equal to
$48.6^@"C" - 23.0^@"C" = 25.6^@"C"$
you can say that you will need
$25.6 color(red)(cancel(color(black)(""^@"C"))) * overbrace("11.877 cal"/(1color(red)(cancel(color(black)(""^@"C")))))^(color(blue)("for 55.5 g of Al")) = color(darkgreen)(ul(color(black)("304 cal")))$
The answer is rounded to three .