Calculate the final temperature that results from mixing 245 grams of cobalt, specific heat 0.446 J/g0C, at 1420C with 106 grams of water at 24.80C.
Heat needed to raise water to 100 C:
heat needed to change water to steam
Heat needed to raise steam from 100 to Tf.
Now, heat given off by cooling Cobalt:
sums of heats = 0
Now solve for and easily get your answer.