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Let $A\left(G\right)$ be the adjacency matrix of $G$. The characteristic polynomial of the adjacency matrix $A$ is called the characteristic polynomial of the graph $G$ and is denoted by $\phi (G,\lambda )$ or simply $\phi \left(G\right)$. The spectrum of $G$ consists of the roots (together with their multiplicities) ${\lambda }_1\left(G\right)\ge {\lambda }_2\left(G\right)\ge ...\ge {\lambda }_n\left(G\right)$ of the equation $\phi (G,\lambda )=0$. The largest root ${\lambda }_1\left(G\right)$ is referred to as the spectral radius of $G$. A $‡$-shape is a tree with exactly two of its vertices having maximal degree 4. We will denote by $G(l_1,l_2,...,l_7)$ $(l_1\ge 0$, $l_i\ge 1$, $i=2,3,...,7)$ a $‡$-shape tree such that $G(l_1,l_2,...,l_7)-u-v=P_{l_1}\cup P_{l_2}\cup ...\cup P_{l_7}$, where $u$ and...