\[\boxed{\mathbf{4.}\mathbf{127}}\]
\[\textbf{а)}\ t = - 3,5{^\circ}С;\ \ t = - 4,5{^\circ}С;\ \]
\[\ t = - 2,5{^\circ}С;\ \ t = - 3{^\circ}С;\]
\[\ \ t = - 4{^\circ}С.\]
\[\textbf{б)}\ t = - 1{^\circ}С;\ \ t = - 2{^\circ}С;\ \]
\[\ t = 0{^\circ}С;\ \ t = - 0,5{^\circ}С;\ \]
\[\ t = - 1,5{^\circ}С.\]
\[\textbf{в)}\ t = 0{^\circ}С;\ \ t = - 1{^\circ}С;\ \ t = 1{^\circ}С;\ \]
\[\ t = 0,5{^\circ}С;\ \ t = - 0,5{^\circ}С.\]
\[\textbf{г)}\ t = 2{^\circ}С;\ \ t = 1{^\circ}С;\ \ \ t = 3{^\circ}С;\ \]
\[\ t = 2,5{^\circ}С;\ \ t = 1,5{^\circ}С.\]
\[\textbf{д)}\ t = 3,5{^\circ}С;\ \ t = 2,5{^\circ}С;\ \ \]
\[t = 4,5{^\circ}С;\ \ t = 4{^\circ}С;\ \ t = 3{^\circ}С.\]