After the first use of 'astronaut'
The sea is used as a symbol for life and its hardships.
Santiago's hand become a religious symbol in two ways. First, the wounds Santiago suffers on his palms are an obvious connection to Christ, especially his crucifixion.
The Mast symbolize the cross
"The rate of change of momentum of an object is directly proportional to the resultant force applied and is in the direction of the resultant force."
James is smarter than Steven. Since smarter is already used to show that James has a higher mental ability than Steven, there is no need for "more"